Trim and heeling board device for boats



Feb. 27, 1968 B. E. ILON 3,370,561

TRIM AND HEELING BOARD DEVICE FOR BOATS Filed Oct. 19, 1966 2Sheets-Sheet 1 INVENTOR FIG. 4. BENGT ERLAND ILON ATTORNEYS Feb. 27,1968 B. E. ILON 3, ,5

TRIM AND HEELING BOARD DEVICE FOR BOATS Filed Oct. 19, 1966 2Sheets-Shee1 2 INVENTOR. BENGT ERLAND ILON BY M QOWCMJMLI ATTORNEYSUnited States Patent C) 3,370,561 TRIM AND HEELING BOARD DEVECE FGRBOATS Bengt Erland Ilon, 43 Strornkarlsvagen, Bromma, Sweden Filed Get.19, 1966, Ser. No. 587,807 Claims priority, application Sweden, Apr. 25,1966,

7 Claims. (Cl. 114-665) This invention relates to a trim and heelingboard device for boats.

It becomes more and more common to provide boats with trim boards of onekind or the other. Such trim boards are used for stabilizing purposes,particularly in order to prevent alterations of the position or rollingof the boat in relation to its traverse horizontal axis through thecenter of gravity. The trim boards used for this purpose generallycomprise plates which in the normal position are approximatelyhorizontal, and to which, dependent on the position of the boat, isimparted the necessary angular setting in relation to the direction oftravel of the boat by manual operation by means of electrohydraulicactuating means, so that the intended stabilization of the position beachieved. Such stabilizers will for natural reasons be fairlycomplicated and hence expensive, and in order to maintain stability theymust also be subjected to constant survey and adjustment, whichnaturally also highly reduces the value of such arrangements.

By means of the present invention, the object of which is a trim andheeling board for boats, the above drawbacks are avoided.

The invention will be described more in detail hereinafter withreference to the accompanying drawings.

In the drawings:

FIG. 1 is a port side diagrammatic View of the rear portion of a boatprovided with a trim and heeling board device of the invention;

FIG. 2 shows a rear elevation of the structure of FIG 1;

FIG. 3 is a diagrammatic port side view of a further embodiment of theinvention;

FIG. 4 is a diagrammatic port side view of a further embodiment of theinvention;

FIG. 5 is a port side diagrammatic view of the rear portion of a boatprovided with a modified trim and heeling board of the invention; and

FIG. 6 is a rear elevation of the structure of FIG. 5.

The trim and heeling board illustrated in FIGS. 1 and 2 comprises alevel board or plate 1 of sheet metal or any other suitable rigidmaterial. The plate 1 is braced by means of stays 2 of iron or the likeattached to the same and simultaneously forming suspension means for theplate, which, in its normal position is assumed to provide a directextension of the bottom 3 of the boat. By means of pivot pins 4 stays 2are pivotally mounted onto the' lower ends of two fore and two rearlinks 5 and 6, respectively, which in turn at their upper ends arepivotally mounted by pins 7, 8. Pins 7 are supported by lugs 11projecting from a support plate arranged on a boat transom 9. The pin 8is carried by a yoke 12 directed approximately horizontally and the freeleg ends of which are pivoting on the pivot pins 7. An inclining stay 13is at its ends by means of pins 14, 15 linkably connected to the yoke 12and the support plate 10. The stay consists of two parts, which are kepttogether by means of a sleeve 16 having one right and one left thread.In this way it is possible to adjust the length of the stay 13 withincertain limits and the inclination of the plate 1 may be set, so that itobtains a normal or initial position suitably adapted to the boat ineach special case, and in which position the foremost edge of the platemay possibly abut on the transom 9. An extension coil spring 17 isinserted, for example, between the support plate 10 and a cross bar 18arranged between the rear links 6. This spring tends to bring the plateto the position just mentioned. In FIG. 2 the line 19 represents theplane of symmetry of the boat hull. Thus only the left half of the boatis shown in this figure. The right half of the transom 9 has a trim andheeling board, which is symmetrically positioned in respect of line 19and identical to the trim and heeling board shown.

The device described hereinbefore operates in the following manner:

Assuming that the stem of the boat during its travel rises relative tothe stern, for example, by an increase in the load at the stern, i.e.,that the angle between the longitudinal extension of the boat, thefore-and-aft line, and the direction of travel of the boat increases,the force of current acting on the trim and heeling board of the waterin which the boat is moving forward will increase due to the increase inthe angle of attack of the water. This in turn results in the plate 1and the links 5, 6 being moved backwards from the transom, for example,to the position indicated by dashed lines. As will be clear, thisdisplacement brings about an increased inclination of the plate by theelfect of the four link mechanism formed by the plate 1, the links 5, 6and the yoke 12. In this way the plate provides a supplementary liftingforce for the boat stern, so that the primarily assumed relative raisingof the boat stem will be opposed and totally or partly prevented. Insuitably adapting the restoring force by the spring 17 and the magnitudeof the angular alteration of the plates position, which is defined bythe length relations of the fore and rear links and their mutualinclination, such a trimming of the boat is possible, that during hertravel the boat will practically maintain a constant angular position asto the inclination of the fore-and-aft line independent of any possibledisplacement of the center of gravity in the longitudinal extension ofthe boat. The etfect will, of course, be the same when the equilibriumof the boat is disturbed in other Ways, for example, by waves. The trimand heeling boards have a stabilizing eifect also in respect of theboats rolling about a foreand-aft line, so called heeling, in whichcase, however, it is mainly the bevelling function of the boards thatwill be utilized.

The trim and heeling board shown in FIGS. 1 and 2 is arrangedperpendicularly to the plane of symmetry of the boat hull. However,particularly in boats having a V- shaped bottom, it may be convenient tolet the two trim and heeling boards incline towards the plane ofsymmetry of the hull, since their stabilizing effect will be increasedin this Way.

The automatic displacement of the trim and heeling board in thelongitudinal extension of the boat and the alteration of the anglenecessary in this connection may be achieved by other means than thefour link suspension illustrated in FIGS. 1 and 2. A trim and heelingboard 20 may, for example, as seen in FIG. 3, be provided with pins 20Aor the like displaceably disposed in bent or angular slots or grooves21, arranged in brackets or arms 22 (only one being shown) projectingfrom the boat transom 9. Board 20 is biased forwardly by spring 20B.Alternately it is also possible, as shown in FIG. 4, at the boat transom9 to arrange a bracket 23 directed downwards and at the lower end ofwhich arms 24 (only one being shown) attached to the trim and heelingboard 26 are pivotally suspended by means of pivot pins 25. A spring 27biases board 26 forwardly.

The embodiment according to FIG. 5 is provided with rear links 28 whichare longer than fore links 29, the upper pivot pin 30 of the links 28being straight above lower pivot pins 31 but positioned higher than theupper pivot pins 32 of links 29. In the resting position of the devicethe links 28 are about vertically directed and substantiallyperpendicular to the level board 33, whereas links 29 are inclined andhave their lower pivot pins 34 somewhat behind the upper pivot pins 32.Due to the performance of the apparatus according to FIG. 5, theredoesnt need to be any spring corresponding to the spring 17 shown inFIG. 1, since the weight of the lower moving parts urges the board 33towards the stern when it is moved in a direction away from the stern.Also here the level board or plate 33 is provided with stays 35 for itssuspension and provides as shown in the drawing, in its normal orresting position a direct extension of the bottom 36 of the boat. Lugs37 project from a support plate 38 arranged on the boat transom 39. Ayoke 40 carries the pin 30, and an adjustable inclining stay 41= is atits ends linkably connected to a support plate 42 and the yoke 40.Support plate 42 is secured to transom 39.

Due to the arrangement of the links '28, 29 and their pivot pins asdescribed above, a very small displacement backwards of the lower pivotpins 31 of links 28 corresponds, when said links are swinging abouttheir upper pivot pin 30, to a rather great displacement backwards andupwards of the pivot pins 34, and hence to a great angular motion of theplate 33 about the centers of the pivot pins 31 and this is a veryfavorable fact.

Further embodiments within the scope of the invention may also beconsidered, and the invention is not limited to any definite kind ofvessels. 7

What is claimed is:

1. In combination with a boat:

a trim and heeling board,

means mounting said board adjacent the stern of the boat adjacent thewater to provide for a downward 4 inclining of the board as it movesrearward from the stern,

means urging the board towards the stern and overcoming the forceexerted by relative movement between the boat and the water to maintainit adjacent the stem with the boat at the desired trim and permit it tomove rearwardly when the trim is such that the:

bow is high relative to the stern.

2. The combination of claim 1 in which the urging means is a spring.

3. The combination of claim 1 in'which the angle of inclination of theboard increases with an increase in the rate of relative movementbetween the boat and the water.

4. The combination of claim 1 in which the means mounting the boardcomprises a fourbar linkage.-

5. The combination of claim 1 in which the means mounting the boardcomprises a slot and a guide pin for following the slot.

6. The combination of claim 1 in which the means mounting the boardcomprises a downwardly extending arm pivoted'to a bracket extendingbelow the stern.

7. The combination of claim 4 in which the four bar linkage comprises afore link and a rear link the upper ends of which links are pivotallyconnected to one member and the lower ends of which are pivotallyconnected to the level board, the rear link being longer than the .forelink and, in its normal position about vertical and at leastsubstantially perpendicular to the level board.

References Cited UNITED STATES PATENTS 3,046,928 7/1962 Sherrill 1l466.5

ANDREW H. FARRELL, Prim'ary Examiner.

1. IN COMBINATION WITH A BOAT: A TRIM AND HEELING BOARD, MEANS MOUNTINGSAID BOARD ADJACENT THE STERN OF THE BOAT ADJACENT THE WATER TO PROVIDEFOR A DOWNWARD INCLINING OF THE BOARD AS IT MOVES REARWARD FROM THESTERN, MEANS URGING THE BOARD TOWARDS THE STERN AND OVERCOMING THE FORCEEXERTED BY RELATIVE MOVEMENT BETWEEN THE BOAT AND THE WATER TO MAINTAINIT ADJACENT THE STERN WITH THE BOAT AT THE DESIRED TRIM AND PERMIT IT TOMOVE REARWARDLY WHEN THE TRIM IS SUCH THAT THE BOW IS HIGH RELATIVE TOTHE STERN.